1. Field of the Invention
The present invention relates generally to a game controller and more particularly, to a button structure used in a game controller, which controls the value of the output signal subject to the contact area between a metal conducting portion and a continual resistor strip or continual carbon film that is controlled subject to the biasing angle of the button or the value of the pressure applied to the button.
2. Description of the Related Art
Following fast development of computer game technology, video games have the characteristics of high resolution, high precision, and high control level. All manufacturers for game machines and related parts are trying hard to improve game precision performance.
FIG. 1A is a top plain view of a game controller 10′ according to the prior art. As illustrated, the game controller comprises a frame shell 11′, and a plurality of key switch buttons 12′ and a cross button 18′ mounted on the frame shell 11′. As shown in FIG. 1B, each key switch button 12′ is vertically movably mounted is a hole on the frame shell 11′ and supported on a rubber member (rubber cone) 13′ at a printed circuit board 15′. The rubber member 13′ has a metal conductor 14′ fixedly disposed on the inside and spaced above two metal contacts 16′ and 17′ at the printed circuit board 15′. When the button 12′ is not pressed, as shown in FIG. 1B, the metal conductor 14′ is kept spaced above the metal contacts 16′ and 17′. When the button 12′ is pressed, as shown in FIG. 1C, the metal conductor 14′ is forced into contact with the metal contacts 16′ and 17′, causing the printed circuit board to output a digital control signal for game control. The rubber member (rubber cone) 13′ returns to its former shape when the applied force is disappeared, and therefore the button 12′ is retuned to its former position by the rubber (rubber cone) 13′.
The method of the aforesaid prior art design in which one digital signal is outputted upon each press of each button 12′ of the game controller 10′ by the player cannot satisfy the variable operation feature of a sophisticated game software problem. Similarly, the aforesaid cross button 18 outputs a corresponding digital signal when the up, down, left, or right button is pressed.
FIG. 18 is a schematic circuit block diagram of a touch-control game controller according to the prior art. According to this design, the touch-control game controller comprises a plurality of control points 80 and 81, a touch sensitive circuitry 82, a ciagonal control circuitry 83, and a computer interface circuitry 84. The control points 80 and 81 are to be selectively triggered by the player's finger 85. The ciagonal control circuitry 83 and the computer interface circuitry 84 are adapted to detect the impedance of the player's finger(s) 85 touching the control points 80 and 81. The touch sensitive circuitry 82 is adapted to scan triggering of one single control point. The ciagonal control circuitry 83 is adapted to scan triggering of multiple control points (for example, for controlling oblique movement of a role in the game). When the player touches one or multiple control points with one or multiple fingers 85, the touch sensitive circuitry 82 or ciagonal control circuitry 83 is induced to output a corresponding control signal to the game machine main unit through the computer interface circuitry 84. However, because the area and elasticity of the finger pads of different users or the value of electrical charges carried in the finger pads of different users are different, the game controller may be unable to define every instruction give by the player precisely. Further, when playing an exciting game or shooting game, the sweat of the finger that touches one or multiple control points may cause a contact error, or shorten the working life of the game controller.
Therefore, it is desirable to provide a button structure for game controller that eliminates the aforesaid problems.